function newDel31() {
	randomnumber2 = getRandomInt(1, 9);
	randomnumber1 = randomnumber2*
		getRandomInt(Math.ceil(100/randomnumber2), 99);
	right_ans = randomnumber1/randomnumber2;
	temp_ans_rank = define_rank(right_ans);
}

function Start() {
	operation_sign = "/";
	operation = "Del";
	operation_func = newDel31;
	left_rank = 3;
	right_rank = 1;
	ans_rank = -1;
	document.documentElement.addEventListener("keydown", keyHandler, false);
	timer();
	newTask(operation_func);
}

function getScore(right_count, wrong_count) {
	return 10*right_score - 15*wrong_score;
}